Human agin gis accompanied by a gradual decline in fat free mass. Although energy intake and expenditure tends to decline with age, body weight usually increases. It is also well documented that aging is associated with a decline in growth hormone levels. (GH) which may contribute to the changes in body composition and amino acid metabolism also described in the elderly. The purpose of this study is to describe anthropometry, growth hormone (GH) and insulin Like Growth Factor-1 (IGF-1) levels leucine kinetics, protein turnover (PT) and energy expenditure (REE) in healthy elderly men (n-46) and women (n-34). Age average was 71.3+4.4 years. Protein turnover (PT) was estimated from leucine kinetics, using a primed constant infusion of [1-13C] Leucine tracer.